Embodiments of the invention relate to a method and a system for diagnosing a waste gate valve malfunction in a power generation system. More particularly, embodiments of the invention relate to a method and an engine controller capable of diagnosing the waste gate valve malfunction based on an operating condition of a throttle valve, and related power generation system.
Combustion engines such as internal combustion (IC) engines are used in a wide range of applications. Typically, a power generation system employing such a combustion engine is equipped with a turbocharger that improves an overall performance of the power generation system. In general, the turbocharger includes a compressor and a turbine mechanically coupled to the compressor via a shaft. An exhaust gas generated by the combustion engine drives the turbine which in-turn drives the compressor via the shaft. When driven, the compressor pressurizes an intake air to generate a pressurized air. The pressurized air typically flows into the combustion engine through a throttle valve and an intake manifold.
Typically, one or both of an amount of compression of the intake air (for example, a percentage compression or a compression ratio) and a rotational speed of the turbine defines an output of the turbocharger. Controlling the output of the turbocharger to obtain a desired engine performance may be desirable. For example, a high output from the turbocharger may result in erratic engine performance and may permanently damage engine's components. Whereas, a lower output from the turbocharger may result in engine hesitation and loss of power.
The output of the turbocharger may be controlled by employing a waste gate valve in the power generation system. Typically, the waste valve is fluidly coupled between the exhaust manifold and an exhaust pipe. The waste gate is operated such that at least a portion of the exhaust gas bypasses the turbocharger. Accordingly, by appropriately controlling an amount of the exhaust gas that bypasses the turbocharger, a rotational speed of the turbine of the turbocharger is controlled to achieve a controlled turbocharger output.
Therefore, malfunctioning of the waste gate valve may adversely impact the engine performance, power output, and fuel economy. Waste gate valves which are coupled fluidly typically do not contain electronic sensors for detection of malfunction. Absence of the electronic sensors makes it challenging to detect malfunction of the waste gate valve. Thus, there is a need for a method and a system for diagnosing the waste gate valve malfunction.